There is a continuing need to improve electrical connectors to meet rigid performance standards imposed by severe environmental requirements established by aerospace applications. During mating and unmating, electrical connectors should be easily and quickly coupled and decoupled with the use of reasonable forces. Once mated and in use, however, connector assemblies must remain connected despite vibrational and/or other forces which might be applied to the connector assembly and which might tend to uncouple the connectors.
Several prior art patents have addressed themselves directly or indirectly to the problem of maintaining an assembled pair of cylindrical electrical connectors together. An approach disclosed by U.S. Pat. No. 2,984,811 to Hennessey, et al. includes providing one connector member with a plurality of spaced bayonets which locate within similarly spaced detents carried by a coupling nut when the assembly is fully mated. A prior art patent to Paole, U.S. Pat. No. 3,971,614 discloses interlocking splines. U.S. Pat. No. 2,784,385 to Ennis discloses an outer sleeve being provided with a series of exposed teeth and a spring member attached to a fixed flight to engage these teeth. U.S. Pat. No. 3,784,966 to Clark shows a spring element engaging one of three recesses. These prior art systems for retarding decoupling had the disadvantages of either being unreliable, difficult to make or prone to failure.
Another approach is typified by U.S. Pat. No. 4,109,990 to Waldron et al and by U.S. Pat. No. 4,268,103. In each of these efforts, a single spring member is disposed within a recess of a coupling nut and the spring includes a inwardly extending projection to engage ratchet teeth on the connector member to be mated. While suitable in many applications, the spring member did not always provide positive and secure engagement with the ratchet teeth and the restraining torques sometimes were not sufficient to prevent the decoupling under vibration. Mounting of the four pins shown by Waldron et al required substantial cost to drill the holes and, during interference fitment of the pins into the holes, caused burrs and/or flakes to enter the connector.
Still a further approach is shown by abandoned U.S. patent application Ser. No. 952,900 filed 10-19-78, wherein one end of a spring loaded detent pin is slidably mounted in a radial bore of a coupling nut and the other end biased into engagement with a connector detent.
There is a continuing need to provide electrical connector assemblies with a mechanism that prevents accidental decoupling, that is cheap, reliable, easy to make and assemble and which secures the assembly together.